Influence of monitor display resolution and displayed image size on the spatial resolution of ultra-high-resolution CT images: a phantom study

• Published in: Radiological physics and technology Vol. 15; no. 2; pp. 147 - 155
• Main Authors: Ikushima, Yoichiro, Tokurei, Shogo, Sato, Shusaku, Ikushima, Kojiro, Hashimoto, Noriyuki, Morishita, Junji, Yabuuchi, Hidetake
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01-06-2022; Springer Nature B.V
• Subjects: Color; Computed tomography; High resolution; Image acquisition; Image contrast; Image reconstruction; Image resolution; Imaging; Kernels; Liquid Crystals; Lung - diagnostic imaging; Lungs; Mediastinum; Medical and Radiation Physics; Medical imaging; Medicine; Medicine & Public Health; Nuclear Medicine; Optimization; Phantoms, Imaging; Radiology; Radionuclide Imaging; Radiotherapy; Research Article; Spatial resolution; Tomography, X-Ray Computed - methods; Ultra-high-resolution computed tomography (UHRCT); Phantom; Liquid–crystal displays (LCD); Matrix size; High-contrast resolution; Reconstruction kernel
• ISSN: 1865-0333; 1865-0341
• DOI: 10.1007/s12194-022-00656-4

To determine the optimal display conditions for ultra-high-resolution computed tomography (UHRCT) images in clinical practice, this study investigated the effects of liquid–crystal display (LCD) resolution and displayed image size on the spatial resolution of phantom images acquired using a UHRCT system. A phantom designed to evaluate the high-contrast resolution was scanned. The scan data were reconstructed into four types of UHRCT image series consisting of the following possible combinations: two types of reconstruction kernels on the filtered back-projection method (for the lung and mediastinum) and two types of matrix sizes (1024
2
and 2048
2
). These images were displayed under eight types of display conditions: three image sizes displayed on a 2-megapixel (MP) and 3-MP color LCD and two image sizes on an 8-MP color LCD. A total of 32 samples (four image series × eight display conditions) were evaluated by eight observers for high-contrast resolution. The high-contrast resolution of the displayed UHRCT images was significantly affected by the displayed image size, although the largest (full-screen) displayed image size did not necessarily show the maximum high-contrast resolution. When the images were displayed in the full-screen size, LCD resolution affected the high-contrast resolution of only the 2048
2
-matrix-size images reconstructed using the lung kernel. In conclusion, the spatial resolution of UHRCT images may be affected by LCD resolution and displayed image size. To optimize the clinical display conditions for UHRCT images, it is necessary to adopt an LCD with an adequate resolution for each viewing situation.